.calculator {
    width: 300px;
    margin: 50px auto;
    border: 1px solid #ccc;
    border-radius: 5px;
    padding: 10px;
    box-shadow: 0 0 10px rgba(0, 0, 0, 0.1);
    background-color: #f9f9f9;
}

.display {
    width: 100%;
    height: 50px;
    margin-bottom: 10px;
    font-size: 24px;
    text-align: right;
    padding: 5px;
    box-sizing: border-box;
    border: 1px solid #ddd;
    border-radius: 3px;
    background-color: white;
}

.buttons {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 5px;
}

button {
    height: 50px;
    font-size: 18px;
    border: 1px solid #ddd;
    border-radius: 3px;
    background-color: white;
    cursor: pointer;
}

button:hover {
    background-color: #a5d6f7;
}

.operator {
    background-color: #f0f0f0;
}

.equals {
    background-color: #4CAF50;
    color: white;
}

.clear {
    background-color: #f44336;
    color: white;
}